Module 1: Cells as the Basis of Life Flashcards
(139 cards)
1
Q
What are prokaryotic cells?
A
Primitive, simple cells that do not have a nucleus
2
Q
What are the four main structures in prokaryotic cells?
A
Cell membrane
Cytoplasm
Ribosomes
Genetic material
3
Q
What is the cell membrane?
A
A structure that surrounds and encloses a cell
4
Q
What is the cytoplasm?
A
The fluid part of the cells, outside of the nucleus that contains chemical substances
5
Q
What are ribosomes?
A
Very small structures found in cytoplasm which manufacture proteins
6
Q
What is genetic material?
A
DNA which contains all information of the cell.
7
Q
What is the plasmid?
A
It is the circular ring of genetic material in prokaryotic cells
8
Q
Which came first prokaryotic or eukaryotic cells?
A
Prokaryotic
9
Q
What are the two main groups of prokaryotic cells?
A
Bacteria and archaea
10
Q
What are eukaryotic cells?
A
Much more complex cells characterised by a membrane bound nucleus
11
Q
What are ogranalls?
A
An internal structure of a cell enclosed by a membrane and has a function
12
Q
What are organisms that contain eukaryotic cells known as?
A
Eukaryotes
13
Q
What is the magnification of a light microscope?
A
x1500
14
Q
What type of specimens can be viewed by light microscopes?
A
Living and non-living
15
Q
What are two advantages of light microscopes?
A
Inexpensive and live specimens can be viewed
16
Q
What is a disadvantage of light microscopes?
A
Can’t magnify more than 2000
17
Q
What is a TEM?
A
Transmission Electron Microscope
18
Q
How does a TEM work?
A
Electrons pass through the specimen
19
Q
What type of image does a TEM produce?
A
2D
20
Q
What is the most common type of electron microscope?
A
TEM
21
Q
What are two advantages of TEM?
A
Offers the most powerful magnification and high quality images
22
Q
What are two disadvantages of TEM?
A
Sensitive to vibration and electromagnetic fields and are hard to maintain
23
Q
What is a SEM?
A
Scanning Electron Microscope
24
Q
How does SEM work?
A
Bombards solid specimens with a beam of electrons which do not pass through but instead are scattered
25
What type of image does a SEM produce?
3D
26
What is an advantage of SEM?
Has the highest resolution and produces really good quality images
27
What are two disadvantages of SEM?
Very expensive and hard to maintain
28
What is the cell membrane?
A selectively permeable membrane around cells which controls intake of water and other chemicals
29
What is protoplasm?
It is the living content of a cell
30
What are the three things plant cells have that animal cells do not?
Cell wall
Chloroplasts
Large, permanent vacuole
31
What are the two things animal cells have that plant cells do not?
Centrioles
Lysosomes
32
What are the 8 things both animal and plant cells have?
Cell membrane
Cytoplasm
Cytoskeleton
Nucleus
Mitochondria
Endoplasmic reticulum
Golgi body
Ribosomes
33
What is the endoplasmic reticulum?
The network of flattened, interconnected membranes that provide transport
34
What is the difference between rough ER and smooth ER?
Rough have ribosomes attached whilst smooth do not
35
What does rough ER do?
Process protein made by the cell and synthesises lipids
36
What does smooth ER do?
It is the main site of lipid production
37
What are ribosomes and what do they do?
Small organelles made from RNA and protein which produce proteins
38
Where can ribosomes be found?
Free in the cytoplasm or on the surface of ER
39
What do golgi bodies do?
They process, package and sort cells
40
What are lysosomes?
Organelles which contain digestive enzymes which split complex chemical compound into simple ones
41
Where are lysosomes produced?
In the golgi body
42
What is the mitochondria?
The power house of the cell, producing energy in the form of ATP through the process of respiration
43
What type of membrane do mitochondria have?
Double membranes
44
What are cristae?
Fine folds of the inner membrane in mitochondria
45
What is the matrix?
Fluid in the central space of mitochondria
46
What is the vacuole?
A large fluid filled storage sac in the cytoplasm of a cell
47
What is the roll of the vacuole?
It provides support to plant cells
48
What are chloroplasts?
Organelles which are responsible for photosynthesis containing chlorophyll
49
What is chlorophyll?
Is the green pigment which traps sunlight that can then be used for photosynthesis
50
What type of membrane do chloroplasts have?
Double membrane
51
What is the stroma?
It is the liquid part of chloroplasts
52
What are thylakoids?
Stacks of membranes with chlorophyll on it
53
What are grana?
Stacks of thylakoids
54
What are cell walls?
Permeable structure which provides strength and support to plant cells
55
What are centrioles?
Form the spindles which hold chromosomes in a dividing cell
56
What is the cytoskeleton?
Framework which give cells shape and coherence
57
What is the fluid mosaic model?
Model of the structure of the cell membrane
58
What does the fluid mosaic model show?
Shows that the membrane is flexible and has a phospholipid bilayer
59
What forms the phospholipid bilayer?
Two layers of phospholipids
60
What is the structure of a phospholypid?
A head with two fatty acid chains
61
Which part of the phospholipid is hydrophilic?
The head
62
What does hydrophilic mean?
Able to absorb water or dissolve in it
63
Which part of the phospholipid is hydrophobic?
Fatty acid tails
64
What does hydrophobic mean?
Water avoiding or won't dissolve in it
65
Which way are phospholipids positioned in the cell membrane?
Heads are positioned towards the outside and fatty tails face inwards
66
What are adhesion proteins?
Is a protein that links cells together
67
What are transport proteins?
Proteins which allow specific substances to move across the membrane
68
What are receptor proteins?
Proteins which bind hormones and other substances
69
What are recognition proteins?
Proteins which allow the body to recognise it as 'self'
70
What are glycoproteins?
Marker proteins
71
What does permeability depend on?
Molecule size, electrical charge or lipid solubility
72
What molecules find it difficult to penetrate a membrane?
Water soluble molecules
73
What molecules can easily penetrate a membrane?
Lipid soluble molecules
74
What types of molecules are soluble in lipids?
Neutral molecules
75
What types of molecules are not soluble in lipids?
Charged molecules
76
How does water move through the membrane?
By a process called osmosis
77
What is diffusion?
It is the net movement of any molecule from high concentration to low until equilibrium is met
78
What is the only thing that can speed up diffusion?
Temperature
79
What is facilitated diffusion?
The process when channel proteins assist larger molecules in diffusing into cells
80
How do carrier proteins help with diffusion?
They bind to molecules, change shape and release the substance
81
How do channel protein help with diffusion?
Small ions can diffuse rapidly through them
82
What is osmosis?
The movement of water along the concentration gradient
83
What does hypotonic mean?
When the solution around the cells have lower concentrations
84
What does hypertonic mean?
When the solution around the cells have higher concentrations
85
What does turgid mean?
When a plant cell is full of water and no more can enter
86
What is the capsule?
Only found in bacteria and is a layer around it.
87
What is active transport?
Movement of molecules requiring the input of energy
88
Which way do molecules move during active transport?
Low concentration to high concentration
89
What is the concentration gradient?
Movement from high concentration to low
90
What is required for active transport?
Carrier proteins that spans the membranes
91
What is endocytosis?
Changing the shape of the cell membrane to surround a particle and engulf it
92
What is phagocytosis?
A type of endocytosis when a solid particle is engulfed
93
What is pinocytosis?
A type of endocytosis when fluid is engulfed
94
What is exocytosis?
Process by which substances are transported from inside a cell out
95
How does exocytosis happen?
A membrane bound vesicle moves to the cell membrane, fuses with it and then releases its content
96
How does SA:V affect cells?
It affects the movement of substances
97
What type of cells have high SA:V?
Smaller cells
98
What type of cells have lower SA:V?
Larger cells
99
What are inorganic nutrients?
Nutrients that do not contain carbon
100
What inorganic nutrients are required by cells?
Water, minerals, carbon dioxide (for photosynthesis) and oxygen
101
What are the four main organic compounds?
Carbohydrates, Lipids, Proteins and Nucleic Acids
102
What is the purpose carbohydrates?
It is a quick source of energy
103
What is the purpose of lipids?
Energy storage and form the structural component of membranes and hormones
104
What is the purpose of protein?
They form structural components in cells and tissues
105
What is the purpose of nucleic acids?
They are storage and expression of genomic information
106
What are carbohydrates made up of?
CHO
Carbon, hydrogen and oxygen
107
What are lipids made up of?
CHO
Carbon, hydrogen and oxygen
108
What are proteins made up of?
CHON
Carbon, hydrogen, oxygen and nitrogen
109
What is nucleic acid made up of?
CHONP
Carbon, hydrogen, oxygen, nitrogen and phosphorus
110
What are monosaccharides?
Simple sugars made up of from one sugar compound such as glucose
111
What are disaccharides?
Complex sugars made from 2 sugar compounds
112
What are polysaccharides?
Complex polymer sugars made from many sugars
113
What form are lipids most commonly found in?
Triglyceride
114
What are the building blocks of proteins?
Amino acids
115
What do amino acids form?
Peptides and polypeptides
116
What are the two types of nucleic acids?
RNA and DNA
117
What are enzymes?
They are biological catalysts which control all metabolic reactions in living cells
118
What are enzymes made from?
Protein molecules
119
What is the active site in an enzyme?
The surface of the enzyme with a specific shape
120
What are substrates?
The molecules which undergo chemical reaction on the active site of an enzyme
121
What is the Lock and Key Model?
Model of the enzyme where the active sight is rigid
122
What is the induced Fit Model?
It is the currently accepted version and is that the active sight is not rigid
123
How does temperature impact enzyme activity?
As temperature increases the rate of reaction also increases until optimal temperature
124
What happens if enzymes are exposed to very high temperatures?
They become denatured and can no longer be used
125
How does PH impact enzyme activity?
Each enzyme has its own narrow range of PH it can function in
126
What happens if enzymes are exposed to extreme PH levels?
They become denatured and can no longer be used
127
How does substrate concentration impact enzyme reactions?
Higher concentrations increases enzyme reactions until all enzymes are used / reaching saturation point
128
What is the word equation for photosynthesis?
carbon dioxide + water --> glucose + oxygen
129
What are the two stages of photosynthesis?
Light dependent stage (photolysis) and light independent (carbon fixation)
130
Where does the photolysis stage occur?
In the grana
131
What occurs during the photolysis stage?
Light energy is absorbed in the thylakoid membranes and water is split into H+ and 02 and ATP is formed
132
Where does the carbon fixation stage occur?
In the stroma
133
What happens in the carbon fixation stage?
CO2 and H+ combine to form glucose
134
When does anaerobic cellular respiration occur?
When there is a lacking amount of oxygen
135
What are the two common biochemical pathways in anaerobic cellular respiration?
Alcohol fermentation and lactic acid fermentation
136
What happens in alcohol fermentation?
Breakdown of glucose to form ethanol + CO2 + ATP
137
What happens in lactic acid fermentation?
Breakdown of glucose to form lactic acid + ATP
138
When does aerobic cellular respiration occur?
When there is a lot of oxygen available
139
What is the formula for aerobic cellular respiration?
glucose + oxygen --> carbon dioxide + ATP
